February 22nd, 2015
The emerging scientific picture of aging is that it is little more than a process of cellular damage that accrues over time. Collected areas of damaged cells give rise to all sorts of problems, including broken arterial walls, arthritic joints, Alzheimer’s; the list goes on and on.
In the field of molecular biology, efforts to quantify the specific processes of damage and degeneration has culminated with new research from the University of California Berkeley, where assistant professor of nutritional science and toxicology Danica Chen has honed in on a class of proteins called surtuins, understood for some time to regulate aging.
One particular surtuin, SIRT3, has been shown to play an important role in assisting blood stem cells of older mice cope with the oxidation that occurs during the aging process. When blood stem cells were infused with SIRT3, new blood cells were regenerated, evidence of a reversal in age-related degeneration of cellular function.
‘We know aging can be regulated so we may be able to manipulate the molecular pathways and slow down the process,’ said Chen, “But there’s never been a demonstration where we could reverse age.
It’s really the next big step.’ Molecular biologist Cynthia Kenyon pioneered research on aging when she published a paper in Nature in 1993 on the tiny worm C. elegans, whose lifespan could be doubled with a single gene mutation. Kenyon’s research was cited in Chen’s recently published work. ‘We know there are a lot of techniques out there,’ said Chen. ‘For example, you can use transgenic mouse models to upregulate sirtuins,’ [increasing the overall quality of a cell] ‘but those only address the question of whether you can slow aging. But you can’t really address the question of whether you could reverse aging.’ Our natural antioxidative system struggles to care for our cells as we age. SIRT3 is seen as a strong candidate to provide a much-needed boost to our antioxidant system.
‘We’re particularly interested in SIRT3,’ Chen said, ‘what we show here is that oxidative stress-induced damage, in fact, is reversible.’ Human trials and gene therapy are likely to be several years away, but with refined techniques, molecular biology could prove to enhance the overall quality of human life, especially in our advancing years.
Image: Wikimedia Commons
Source: Brown K, Xie S, Qiu X, Mohrin M, Shin J, Liu Y, Zhang D, Scadden D, & Chen D (2013) SIRT3 Reverses Aging-Associated Degeneration Cell Reports DOI: 10.1016/j.celrep.2013.01.005
Tags: how human cells regenerate, cells disease, necrosis cell